The invention relates to a microwave component.
German patent application 196 36 840.5 describes a microwave component which comprises a substantially tub-shaped housing part with a bottom portion and at least one wall portion merging into the circumference of the bottom portion, and a lid part, the housing part and lid part surrounding an inner space. A number of substantially disc-shaped components are arranged in a stack in this inner space between the bottom portion and the lid part. Adjoining the stacked arrangement of the components, at least one magnetically non-permeable spacer element is provided between the bottom portion and the lid part adjoining the stacked arrangement of the components over at least substantially the entire height of the inner space. This spacer element is provided for filling up an intermediate space between the stacked arrangement of the components and the wall portion(s) with matching shape along at least part of that dimension of the wall portion(s) which extends at least substantially in the direction of the circumference of the bottom portion. The magnetically non-permeable spacer element may in this case be made from an electrically non-conducting material and not only serves as a mechanical retaining, device but also as an electrical insulation. The spacer element may in particular have a high dielectric constant. It is thus possible for at least a substantial portion of the intermediate space between the stacked arrangement of the components and the wall portion(s) to be filled up with a (material having a) high dielectric constant. In the cited patent application, it is further indicated that this space may be advantageously utilized for compact electrical or electronic circuit elements.
The present-day development of generic microwave components leads to a desire for ever more compact constructions with ever smaller dimensions, for various reasons. Among these reasons are on the one hand the continuing miniaturization of appliances in which such microwave components are used, and on the other hand also the operation of these microwave components at ever higher operating frequencies. This also relates to microwave circulators and microwave isolators which are usually constructed as microwave circulators with a built-in load impedance. In the usual construction thereof, the load impedance is arranged at the same level as a microwave guiding arrangement, such as used in a manner known per se in microwave circulators. This arrangement of the load impedance, however, has the disadvantage that a very large space must be provided for the load impedance at the level of the microwave guiding arrangement, especially if it is dimensioned for a high electric power dissipation. This means that a base surface of the bottom portion of the housing part of the microwave component extending in the direction of the plane of the microwave guiding arrangement must also have very large dimensions if the load impedance is to be enclosed by the housing part. This, indeed, is desirable for reasons of circuit and manufacturing technology.
The invention has for its object to improve a microwave component of the kind described above such that a compact construction which promotes miniaturization is obtained in spite of the inclusion of a larger load impedance.